PyMOTW: base64

The base64, base32, and base16 encodings convert 8 bit bytes to values with 6, 5, or 4 bits of useful data per byte, allowing non-ASCII bytes to be encoded as ASCII characters for transmission over protocols that require plain ASCII, such as SMTP. The “base” values correspond to the length of the alphabet used in each encoding. There are also URL-safe variations of the original encodings that use slightly different results.

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